Liquid-screening apparatus



G. R. RODDY. LIQUID SCREENING APPARATUS.

' I APPHCATION ED JAN.19,192I- 1,417,205. Patented May 23, 1922..

2 SHEETS-SHEET 1.

e. R. RODDY. LIQUID SCREENING APPARATUS. APPLICATION FILED JAN.19, 192I-Patented May 23, 1922 2 SHEETS-SHEET 2.

UNWEE STATES GUSTAV R. BUDDY, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO CHAINBELT COM- PANY, OF MILW'AUKEE, VIISCONSIN, A OG'REQRATION OF VJISCONSIN.

LIQUID-SCREENING APPARATUS.

r n mos.

To all whom it may concern:

Be it known that I, GUs'rAv R. Ronny, a citizen of the United States,residing at Mil-- waukee, in the county of hlilwaukee and State oflVisconsin, have invented certain new and useful Improvements in Liquid-Screening Apparatus, of which the following is a specification.

This invention relates to endless traveling water screens such as areemployed to treat sewage water taken from streams and used forindustrial purposes, etc.

In the use of apparatus of this kind the water to be screened is usuallytaken through channel comprising a chamber into which one end of thescreen is inserted, while its upper end extends above the liquid level,that the material collected thereby may be the more easily removed.Acommon form of liquid screen consists of a series of perforated metalplates secured to endless chains and operated so that the upper, andupwardly moving, run thereof, is the one that performs the separatingaction. Such a screen is usually mounted in a rigid framecarryingthewheels with which the chains carrying the screening platesengage, and this is usually hinged, so that the frame may be let downinto. the screen-ingchamber of the waterway or maybe lifted therefromwhen not in use or when requiring repairs.

When apparatus of-this kind is in use, the water upon one side of thescreen,the side toward the intake ofthe conduit,-is fouled with thematerial the screen is intended to remove, while that on the other side,having passsed through the screening surface, is cleansed ofthe materialthe screen removes; and inorder that the separationbetweeen thescreenediand unscreened bodies of water may be maintained as perfect aspossible, so as to insure that all the water that flows through theconduit shall pass through the screening surface, andnot around thesides or ends thereof, various sealing means have been devised.

My invention relates to such sealing means.

In the accompanying drawings- Figure 1 is a view, parts in longitudinalsection and others in elevation, of a liquid Specification of LettersPatent. Paigntefl ltflay 23, 11922.

Application filed January 19, 1921. Serial No. 438,487.

on the line II-II of Fig. 1 on a larger scale than Fig. 1.

Fig. 3 is a longitudinal sectional view taken through the lower,immersed, end of the screen.

Fig. t is a transverse sectional view on the line IV-IV of Fig. 8.

In the drawings A represents a frame, hinged at a, and in which operatesan endless traveling liquid screen B. In the frame are mounted thewheels 0 on which are sup ported the screen and about which it turns.The parts thus far referred to may be of widely different specificconstruction, and therefore are not illustrated in detail. The free endof th frame A is adapted to be lowered into a chamber D through whichthe liquid to be screened flows. This chamber is usually built ofconcrete, and is of a little greater wirth than the screen and its frameA.

The direction of movement of the screening surface is indicated by'arrows, the uprun thereof being the working portion. and the body of theliquid above the line of the said uprun and toward. the foot or free endof the screen is the unscreened liquid. while that on the opposite sideof the said uprun of the sc1'een-below the plane of said run and towardthe head of the frame,is the body of cleansed liquid.

In order to form cut-offs separating these bodies of liquid, and locatedbetween the screen frame and the side walls of the chamber D, it hasbeenproposed to secure to or set into the said chamber walls inwardlyprojecting flanges 2 parallel with the working run of the screen, and tohave engaged therewith, by overlaying them, other flanges that aresecured to and projecting from the sides of the screen frame.

In installations of water screens of the type to which my invention isapplied, it is common practice for the party who 1s to be the user ofthe screen to. construct the chamber D and to set the flanges 2 in thewalls thereof, as the screen cannot be put into place until the concreteof which the chamber walls are formed has hardened, and it is desirableto set the flanges 2 at the time the walls are constructed.

But much difficulty has been experienced when this practice has beenfollowed, in getting the flanges on both sides the screen frame toaccurately fit the flanges set in the walls of the chamber. The fit onone side may be accurate and all that is to be desired, while that uponthe opposite side is not accurate and allows a space between theflanges, through which liquid passes unscreened. Various means have beenresorted to to overcome the difficulties just suggested, such as notsetting the wall flanges '2 until the time when the screen is installed,or supporting the screen frame flanges so that they may be adjusted, butthese expedients are not entirely satisfac' tory.

In practicing my invention the wall flanges 2 are put in place when thewall is constructed, being set as nearly to the desired line aspossible. Another set of flanges, 3, are secured to the sides of thescreen frame, projecting laterally therefrom, and being located so thatwhen the screen is installed and let down into the chamber D theflanges, 2 and 3, of each set will lie in the same inclined plane, edgeto edge but separated from each other by a narrow space. This space isthen covered by a separate sealing bar 4 adapted to rest upon the twoflanges, and to cover and close the space between them. The bar ispreferably of T-shape in cross section, and its central rib or flange 5lies in the space between the bars 2 and The flanges 3 are preferablysecured to the screen frame at its upper edges, as represented in Fig.2.

Eye bolts 6 may be fastened to the seal ing bars into which hooks areinserted to facilitate handling the bars in placing and removing them.In place of eye bolts holes may be punched through the bars to receive ahook, but the eye bolts are preferred.

The advantages of the cut-oif arrangement shown is its simplicity ofconstruction, and effectiveness in closing the open spaces between thesides of the screen frame and the side walls of the chamber in which thescreen operates, and its ability to adjust itself to slight variationsin level that may exist between the wall and frame flanges, or

differences in the width of the spaces between the edges of the opposingflanges due to inaccurate construction of the chamber walls, setting ofthe wall flanges 2. or inaccurate mounting of the supports for thescreen.

In using water screening apparatus such as herein described it iscustomaryto have the lower immersed end of the screen frame rest in atransverse recess or pocket formed. therefor in the bottom of thechamber D,

such as indicated at F; and it is necessary that cut-off means,separating the bodies of unscreened and screened water, be provided. atthe said end of the screen. The recess or pocket f facilitates theconstruction and arrangement of the screen foot cut-off, means whichconstitute one of the features of my present invention.

The immersed end of the screen frame, in which the lower sprocket wheelsC are mounted, and where the screen makes the turn from the lower,down-moving run, to the upper, upward moving run, is pref erably closedin by transverse walls 7 the edges of the ends of which approach asclosely as practical to the moving screen sur faces.

Secured to the screen frame A near its lower end are cutoff plates 8 towhich are secured cross bar 9. To the latter is united, by the hinge 10,a crosspiece 11, preferably of angular shape, with one member securedflatwise against the hinge and the other resting against the edges ofthe parts 8 and 9 so as to hold the crosspiece in proper normalposition. A contact piece 12, formed preferably of wood, is supported bythe crosspiece 11. This contact piece is shaped so that its free end 13is adapted to rest upon the upwardly moving screen surface and forms aliquid seal along the lines of its contact. It is adjustably supported,as by means of screwthreaded rods 14, 14, seated in the hingedcrosspiece 11 where they are secured by nuts 15. The threaded portionsof the rods 14 preferably. have engagement with a metal plate lfl seatedin the upper face of the contact piece 12.

A cut-off plate 17, hinged at 18 to the floor of the chamber D near theedge of the recess or pocket F, is adapted to rest upon the cut-offplates 8 and 9. 4

The cut-off plates 8 hax e close engagement .with the transverse wall 7for the lower immersed end of the screen, and, in connection with thehinged plate 17, prevent flow of unscreened water around the end of thescreen frame. The cut-off piece 12 prevents the flow of unscreened waterdown the faces of the upwardly moving screening plates and so under thewall 7, by which path it might reach and become mixed with the body ofscreened liquid.

The cut-off parts here described for the lower end of the screen areall, with the exception of the plate 17, supported directly by thescreen frame. The hinging of the plate 17 permits it to be moved backout of the way of the end of the screen when that is lifted from orloweredinto the pocket F. By hinging the cut-off piece 12 it ispermitted to move should any object caught'by the screen come intoengagement therewith and. be carried past it. The adjustable manner ofsupporting the contact cut-off piece 12 permits it to be accurately setwith reference to the moving screen surface.

Having described my invention What I claim is 2-- 1. In a liquidscreening apparatus comprising a chamber through which flows the liquidto be screened and a frame carrying the screen and adapted to be placedin the said chamber, cut-off means to separate the unscreened and thescreened bodies of the liquid, located between the screen frame and theside walls of the chamber, and consisting of flanges secured to the saidchamber walls and projecting toward the screen frame, and other flangescarried by the screen frame and arranged to lie opposite to the saidwall flanges and in approximately the same plane, but separatedtherefrom by narrow open spaces, and separate s cover plates resting onthe said flanges and closing the open spaces between them.

2. Apparatus such as set forth in claim 1 when the cover plates areT-shaped and the central flanges thereof lie in the spaces between thewall and screen frame flanges.

3. Apparatus of the character stated in claim 1 wherein the screencarried by the frame is an endless traveling screen the uprun of whichconstitutes the working screening surface, and wherein the screen frameflanges of the cut-off are carried by the upper edges of the screenframe.

l. Apparatus of the character stated in claim 1, wherein the screen isan endless traveling one, having cut-off means for separating theunscreened from the screened liquid located at the immersed, foot end ofthe screen, and consisting of a transverse cut-off extending across theuprun of the screen near its lower end and supported from the screenframe.

5. Apparatus such specified in claim 4i in which the transverse cutoffhas a hinge support permitting it to yield to allow material that may becarried upward by the screen to pass.

6. iipparatus such as specified in claim 4, in which the transversecut-off is adjustable toward and from the screening surface.

7. Apparatus such as specified in claim 4, in which the transversecut'off has a hinge support and is also adjustable toward and from thescreening surface.

8. Screening apparatus such as stated in claim 1 wherein the screen isan endless traveling one, having its lower immersed end enclosed by atransverse wall, and the chamber in which the screen operates having arecess in which the said immersed end of the screen is located,transverse cut-off means for preventing the flow of unscreened liquidaround the lower, immersed end of the screen, comprising a plate hingedto the bottom of the chamber, serving to cut off the flow of liquidaround the immersed end of the screen outside the said transverseinclosing wall, and a transverse cut-off carried by the screen frame andheld in close engagement with the moving screen surface and serving toprevent flow of water around the1 screen end inside the said transversewa l.

. GUSTAV R. RODDY.

